In a previous study, aerosolized alprostadil was effective in improving the functional class of the patient, exercise capacity and improved shunting. Large randomized trials are needed to prove the efficacy of this cost effective therapy in patients with pulmonary hypertension and ARDS. Other available therapies like nitric oxide inhalation costs higher around Rs 350/liter and a total of 34-45 liters per patient is required. It is also associated with additional side effects, such as thrombocytopenia.